Process of cleaning washing machines



Patented July 15, 1930 UNITED STATES PATENT OFFICE EDGAR S. STODDARD, OF BERWYN, AND VELMA ALLEN, OF CHICAGO, ILLINOIS, AS-

SIGNORS TO THE CONOVER COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS N0 Drawing. Application filed May 17,

This invention relates to a process of utilizing washing machines and particularly relates to a process of cleansing dish-washing machines of impurities which are deposited in the washing chambers thereof.

Althou h this invention is especially designed to e utilized in connection with dishwashing machines such as those shown and described in applications Serial Nos. 353,841; 193,414; and 262,652, filed January 12, 1920; May 23, 1927 and March 19,-1928, respectively, it is of broader application to other washing machines.

Dishwashing machines shown and described in the above applications are of the self-cleansing type. The dishes and racks are so positioned within the Washing chamber and the cleansing or rinsing liquid spray is so generated that all food and dirt particles will be washed down into the liquid pool at the bottom of the machine and then rea moved from the machine. All crevices or recesses in the washing chamber in which food and dirt particles may collect are eliminated.

However, water from the average public water supply will in time deposit a gray film on the metal dish racks and onthe'inside of the tank. This film principally results from the lime in the water and-it will deposit even if a water softener such as trisodium phosphate is added to the cleansing and rinsing liquids admitted to the washing chamber.

The object of this invention is to provide a simple and efficacious method of removing such deposits from the interior of the washing chamber of the machine which can be performed by the housewife with materials at her command in the kitchen.

The preferred method of this invention comprises washing the interior of the washing chamber with a diluted vinegar or similar acid solution, followed by one or two washings with a water to which an alkaline detergentor a water softener has been added, and finally a washing with hot water free of additions.

A specific embodiment of the invention to which the invention, however, is by no means restricted, will now be described. The inte rior of the washing chamber of the machine PROCESS OF CLEANING WASHING MACHINES 1928. .Serial No. 278,619.

r the swinging inlet arm. In the former application the float valve on the inlet conduit will control the amount of liquid added to the washing chamber while in the latter application the gauge on the side of the machine will indicate when the proper amount of the liquid has been added.- When the five quarts of liquid have been added, two cups of household vinegar are then added and the impeller of the machine is operated for five minutes. The vinegar wash is then discharged.

The machine is next charged with the proper amount of hot water to every five quarts of which has been added two tablespoons of an alkaline detergent or a water softener suchas tri-sodiu'm phosphate. In

.the case of the machines of the above men tioned applications five quarts ofwater are the proper amount'to place in the washing chamber. Themachine is then operated for one minute and is then discharged.

The machine is then preferably subjected to a water-softener rinse. In this operation the machine is charged with hot Water to every five quarts of which is added one tablespoon of the water softener. The machine is then operated for one minute and is then discharged. L

Finally the machine is charged withfresh hot water, is rinsed for one minute and then is discharged. Whereupon the cover is opened and the racks and inside of the machine are allowed to dry by evaporation.

' .This operation of cleansing the machine should preferably be performed every one or two weeks. r It may be desired to modify the above process by the use of a dilute acid wash between the alkaline detergent and the hot water wash free from additions. This acid wash will remove the precipitated salts resulting from the water and the detergent from the walls of the vessel.

Vinegar and trisodium phosphate have been given as preferred examples of an acid material and an alkaline detergent, respectively, which may be used in the process of the present invention. These materials have been specified because of the fact that they are usually readily available in most households. However, if other alkaline detergents or if other acid materials are readily available, they may be used to replace part or all of the spacific alkaline and acid materials mentioned. As ageneral rule, however, vinegar is the only acid material kept in the ordinary household. Alkaline detergents other than tri-sodium phosphate,'however, are frequently= available.

What is claimed is:

1. A process of cleansing a dishwashing machine which comprises adding the normal amount of hot water thereto, adding to such liquid a small amount of vinegar in proportion of about two cups of vinegar to five to seven quarts of water, operating the machine for five minutes, discharging the vinegar wash; again adding the normal amount of hot water to the machine, adding a small amount of tri-sodium phosphate thereto in the proportion of two tablespoons of trisodium phosphate to about every five to seven quarts of water, operating the machine for one minute, discharging the machine; again adding the normal amount of hot water to the machine, adding a small amount of tri-sodium phosphate thereto in the proportion of one tablespoon of tri-sodium phosphate to about every five to seven quarts of water, operating the machine for one minute, discharging the machine; and finally again adding the normal amount of hot water to the machine, operating the machineand then discharging the same. a Y a,

2. A process of cleansing a dishwashing machine which comprises adding the normal amount of hot water thereto, adding to such water a small amount of vinegar, operating the machine for five minutes, and then discharging the vinegar wash; again adding the normal amount of hot water to the machine, adding tri -sodium phosphate thereto, operating the machine and discharging the machine; again adding the normal amount of hot water to the machine, adding half as much tri-sodium phosphate as before to the water, operating and discharging the machine and finally again adding the normal amount of hot water to the machine, operating and discharging the machine.

3.. A process of cleansing a dishwashing machine which comprises washing the interior of the nachine with a diluted vinegar by operating the machine for five. minutes, discharging the vinegar wash, then washing the interior of the machine with hot water containing an alkaline detergent byv operating the machine for several minutes, discharging the machine; and finally washing the machine with fresh hot water.

4. A process for removing deposits of lime soaps and occluded grease from washing machines which comprises adding hot water thereto and sufficient acid material to break up the deposits, removing the acid liquor, then adding an alkaline detergent to neutralize the acidand remove the greasy materials, and then rinsing the machine free of chemical agents with clean water.

5. A process of removing deposits of lime soaps and occluded grease from washing machines which comprises adding hot water thereto and sufiicient acid material to break up the deposits, removing the acid liquor, then adding enough alkaline detergent in solution in hot water to neutralize the acid and remove the greasy materials, and then rinsing the machine free of chemical agents with clean water. 1

, 6. The process of cleansing a dishwashing machine which comprises washing the interior of the machine with a diluted vinegar, removing the vinegar wash, then washing the interior of the machine with a solution of trisodium phosphate, removing the tri-sodium phosphate solution, again washing the intenor of the machine with a tri-sodium phosphate of greater dilution than the previous tri-sodium phosphate, removing the second tri-sodium phosphate wash, and finally washing the machine with fresh hot water.

7. A process of cleansing a washing ma chine which comprises washing the interior of the machine with an acetic acid solution, then washing it with'a solution of tri-sodium phos phate and finally washing it with fresh hot water. 7 I

In testimony whereoT we have hereunto subscribed our names.

EDGAR S. STODDARD. VELMA ALLEN. 

